org.jacoco.core.internal.instr
Class InstrSupport

java.lang.Object
  org.jacoco.core.internal.instr.InstrSupport

public final class InstrSupport
extends Object

Constants and utilities for byte code instrumentation.

Field Summary

static int	ASM_API_VERSION ASM API version
static int	DATAFIELD_ACC Access modifiers of the field that stores coverage information of a class.
static String	DATAFIELD_DESC Data type of the field that stores coverage information for a class ( boolean[]).
static int	DATAFIELD_INTF_ACC Access modifiers of the field that stores coverage information of a Java 8 interface.
static String	DATAFIELD_NAME Name of the field that stores coverage information of a class.
static int	INITMETHOD_ACC Access modifiers of the initialization method.
static String	INITMETHOD_DESC Descriptor of the initialization method.
static String	INITMETHOD_NAME Name of the initialization method.

Method Summary

static void	assertNotInstrumented(String member, String owner) Ensures that the given member does not correspond to a internal member created by the instrumentation process.
static org.objectweb.asm.ClassReader	classReaderFor(byte[] b) Creates a ClassReader instance for given bytes of class even if its version not yet supported by ASM.
static int	getMajorVersion(byte[] b) Gets major version number from given bytes of class (unsigned two bytes at offset 6).
static int	getMajorVersion(org.objectweb.asm.ClassReader reader) Gets major version number from given ClassReader.
static boolean	needsFrames(int version) Determines whether the given class file version requires stackmap frames.
static void	push(org.objectweb.asm.MethodVisitor mv, int value) Generates the instruction to push the given int value on the stack.
static void	setMajorVersion(int majorVersion, byte[] b) Sets major version number in given bytes of class (unsigned two bytes at offset 6).

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

ASM_API_VERSION

public static final int ASM_API_VERSION

ASM API version

See Also:

Constant Field Values

DATAFIELD_NAME

public static final String DATAFIELD_NAME

Name of the field that stores coverage information of a class.

See Also:

Constant Field Values

DATAFIELD_ACC

public static final int DATAFIELD_ACC

Access modifiers of the field that stores coverage information of a class. According to Java Virtual Machine Specification §6.5.putstatic this field must not be final:

if the field is final, it must be declared in the current class, and the instruction must occur in the <clinit> method of the current class.

See Also:

Constant Field Values

DATAFIELD_INTF_ACC

public static final int DATAFIELD_INTF_ACC

Access modifiers of the field that stores coverage information of a Java 8 interface. According to Java Virtual Machine Specification §4.5:

Fields of interfaces must have their ACC_PUBLIC, ACC_STATIC, and ACC_FINAL flags set; they may have their ACC_SYNTHETIC flag set and must not have any of the other flags.

See Also:

Constant Field Values

DATAFIELD_DESC

public static final String DATAFIELD_DESC

Data type of the field that stores coverage information for a class ( boolean[]).

See Also:

Constant Field Values

INITMETHOD_NAME

public static final String INITMETHOD_NAME

Name of the initialization method.

See Also:

Constant Field Values

INITMETHOD_DESC

public static final String INITMETHOD_DESC

Descriptor of the initialization method.

See Also:

Constant Field Values

INITMETHOD_ACC

public static final int INITMETHOD_ACC

Access modifiers of the initialization method.

See Also:

Constant Field Values

Method Detail

getMajorVersion

public static int getMajorVersion(byte[] b)

Gets major version number from given bytes of class (unsigned two bytes at offset 6).

Parameters:

b - bytes of class

Returns:

major version of bytecode

See Also:

Java Virtual Machine Specification §4 The class File Format, setMajorVersion(int, byte[]), getMajorVersion(ClassReader)

setMajorVersion

public static void setMajorVersion(int majorVersion,
                                   byte[] b)

Sets major version number in given bytes of class (unsigned two bytes at offset 6).

Parameters:

majorVersion - major version of bytecode to set

b - bytes of class

See Also:

getMajorVersion(byte[])

getMajorVersion

public static int getMajorVersion(org.objectweb.asm.ClassReader reader)

Gets major version number from given ClassReader.

Parameters:

reader - reader to get information about the class

Returns:

major version of bytecode

See Also:

ClassReader.ClassReader(byte[], int, int), getMajorVersion(byte[])

needsFrames

public static boolean needsFrames(int version)

Determines whether the given class file version requires stackmap frames.

Parameters:

version - class file version

Returns:

true if frames are required

assertNotInstrumented

public static void assertNotInstrumented(String member,
                                         String owner)
                                  throws IllegalStateException

Ensures that the given member does not correspond to a internal member created by the instrumentation process. This would mean that the class is already instrumented.

Parameters:

member - name of the member to check

owner - name of the class owning the member

Throws:

IllegalStateException - thrown if the member has the same name than the instrumentation member

push

public static void push(org.objectweb.asm.MethodVisitor mv,
                        int value)

Generates the instruction to push the given int value on the stack. Implementation taken from GeneratorAdapter.push(int).

Parameters:

mv - visitor to emit the instruction

value - the value to be pushed on the stack.

classReaderFor

public static org.objectweb.asm.ClassReader classReaderFor(byte[] b)

Creates a ClassReader instance for given bytes of class even if its version not yet supported by ASM.

Parameters:

b - bytes of class

Returns:

ClassReader